Wednesday, February 08, 2023, 12:00pm - 01:00pm
This repeat is an exception to the normal repeat pattern
Kyle Kaplan, SOFIA Science Center
How To Absolute Flux Calibrate Your IGRINS Observations: Method and Scientific Application
Abstract
I will present a method for absolute flux calibrating data from the Immersion GRating INfrared Spectrometer (IGRINS) to within 20% or better accuracy using the spectrum of the accompanying standard star. Most IGRINS observations have a hot (typically A0V) standard star observed at a similar airmass for empirical relative flux calibration and telluric correction. This method can be updated to absolute flux calibrate and better telluric correct IGRINS data by estimating the standard star’s PSF and slit-losses during observation and fitting the standard star spectrum with synthetic spectra generated by stellar atmosphere models which are normalized to the star’s photometric magnitudes. I will discuss each step in the process and the unforeseen caveats I encountered such as wavelength dependent slit-losses and spectrally peculiar standard stars. Finally, I will present preliminary results for absolute flux calibrated molecular hydrogen emission lines from the Photodissociation Regions presented in Kaplan et al. (2021) and show how the absolute flux calibrated emission line fluxes can be directly compared to results from different instruments and to radiative transfer models. This method can be used to absolute flux calibrate any IGRINS data with an accompanying standard star observation, enabling new science with existing archival data.
Illa Rivero Losada, The University of Texas at Austin
Magnetic Fields Across the HR Diagram
Abstract
In this talk I will briefly summarize the importance of magnetic fields in the Universe, particularly in the field of stellar astrophysics. I will present some of the challenges of the field, and the impact of stellar magnetic fields on other areas of astrophysics, such as exoplanet characterization and the habitability zone.
Location: PMA 15.216B and online